1. Field of the Invention
The present invention relates to sanitation of a liquid and more particularly pertains to compact, efficient devices used for irradiation of liquids such as those used in foods and food processing. The present invention also relates to liquids sanitized by such devices.
2. Description of Related Art
Food sanitation is a growing concern in the world. More and more aggressive disease causing agents are discovered every year. Moreover, an increasing number of people are made ill each year by eating contaminated foods. Also, the numbers of foods linked to food-caused illnesses continues to increase. Nonetheless, the desire for safer foods is higher than ever. In fact, state and federal jurisdictions are requiring that businesses use the most efficacious food safety and sanitation practices.
Efficient use of modern sanitation techniques decreases the cost of applying them. These savings, when passed to the consumer, mean the consumers spend less on the processed foods. Also, efficient sanitizing techniques can allow more food to be processed in a smaller amount of space. Thus smaller facilities may compete with larger ones, thereby increasing competition between processors and also lowering prices to consumers. In addition, facilities that use less-safe processing techniques may be easily retrofit to install an efficient apparatus. Also, the modularity of a new sanitizing apparatus makes it easy to manufacture and easy to replace parts for the apparatus.
Sanitizing radiation allows a highly controllable application of organism-killing radiation to foods and food additives. The use of sanitizing radiation in the food industry in general is well known in the prior art, and has been used in a variety of forms, including gamma ray radiation, ultraviolet (UV) light and infrared radiation.
For example, it is well known that the use of gamma radiation and UV radiation has been used in some countries for the sterilization of spices and animal feeds. However, over-use of ultraviolet radiation may cause undesirable chemical reactions with a food or food additive, which can cause the food or food additive to obtain undesirable flavors or textures. Also, various vitamins and proteins may be altered or destroyed through being subjected to too much radiation, reducing the food value of the treated product.
Traditional methods of irradiating liquid foods and food additives used an unnecessary amount of space in a food processing facility. They have long conveyors or hard-to-reach pipelines. For example, U.S. Pat. No. 6,150,663 to Rosenthal teaches a system incorporating a pair of stainless steel cones placed end-to-end and jacketed with steel to treat a liquid flowing through a pipeline. The entire system is linear in flow and an inefficient use of space. Moreover, in the prior art different systems are used for different processes. The lack of a modular system makes utilization the sanitizing radiation difficult to apply or manufacture on a large scale, or to retrofit into an existing system.
There is no system designed with modularity in mind, to suit different processes properly, or to provide easy replacement of component parts. There is no system wherein the radiation sources as well as the paths for the liquid to be sanitized are both optimized for radiation treatment and are highly modular in design. There is no system that treats liquid as a thin film, governed principally by its surface tension, thereby allowing sanitization of fluids even with a relatively high opacity. There is no system that is easy to assemble, clean, maintain and disassemble. There is no system using sanitizing radiation which is compact and enclosable, so high levels of the radiation may be used in a small amount of space and still be safe for operators. There is no system which takes advantage of the flowing characteristics of a liquid to form a cascade in a sanitization process, thereby reducing the length that another apparatus providing an equivalent amount of sterilizing radiation would have to take up.
The present invention is a compact, efficient, easy-to-maintain. enclosable apparatus for sanitizing a liquid flowing along a cascade within a cabinet body, having means for directing the liquid along a predetermined path within the cabinet body and means for subjecting the liquid to a sanitizing radiation for a predetermined time while flowing along the predetermined path, whereby the liquid is subject to suffciient sanitizing radiation for a predetermined level of sanitization. In one embodiment, the means for directing the liquid comprises a plurality of downward sloping irradiation, trays whereby liquid travels from one irradiation tray to another irradiation tray. Preferably, the irradiation trays have one or more elements adapted for increasing the turbulent circulation of the liquid, and the liquid is diffused before the liquid reaches an irradiation tray so that the liquid flows generally the width of the irradiation tray. The cabinet body includes an ingress and an egress.
In an alternative embodiment, each irradiation tray comprises a plurality of elements adapted for increasing circulation of the liquid. In another embodiment, the means for subjecting the liquid to a sanitizing radiation comprises one or more. irradiation assemblies in optical contact with the surface of the liquid. In yet another embodiment, the irradiation assembly comprises a UV light source and a UV light shield located between the UV light source and the liquid. In still another embodiment, the irradiation assembly further comprises a rigid reflector shield located between the UV light source and the UV light shield. In yet another embodiment, the reflector shield provides resistance to ease the attachment of the irradiation assembly to the cabinet body and strength to the irradiation assembly to resist damage during maintenance activity including hosing.
In another embodiment, the means for diffusing includes one or more diffusing trays, each diffusing tray including several voids through the bottom surface. In still another embodiment, the irradiation trays have one or more down pipes at a downstream position. The diffusing trays further may include a generally c-shaped splash guard piece, and the down pipe of an irradiation tray above the diffusing tray is in complementary contact with the splash guard. The diffusing tray and the irradiation tray may be easily removable.
In yet another embodiment, the egress includes a sloping bottom interior surface of the cabinet body toward a drain pipe in gravity flow connection with the sloping bottom. In still another embodiment, the amount of radiation exposure to the liquid is a function of the opacity of the liquid, the rate of low of the liquid, the intensity of the source of the sanitizing radiation, the distance between the sanitizing radiation and the liquid, the time the liquid spends under the sanitizing radiation.
In still another embodiment, the invention is an irradiation assembly for use in irradiating a liquid flowing in cascade within an enclosable cabinet, comprising a UV light source. a UV light shield located between the UV light source and the liquid and a rigid internal reflector shield located between the UV light source and the UV light shield. In yet another embodiment, the assembly has an endcap located on each end of the UV light shield for attachment of the assembly within the interior of the cabinet. The endcap may further include a rigid sheath having threads, located around the perimeter of the UV light shield, an endpiece having threads which are complementary to those on the sheath located on the exterior of the cabinet; and a compressive gasket, whereby engagement of the endpiece with the sheath generally seals the assembly to the interior of the cabinet.
In yet still another embodiment, the invention is a compact, efficient, easy-to-maintain enclosable cabinet for sanitizing a liquid having a cabinet body, a plurality of troughs directing the liquid along a predetermined path including a cascade within the cabinet body; and one or more sanitizing radiation sources for subjecting the liquid to a sanitizing radiation for a predetermined time while flowing along the predetermined path, whereby the liquid is subject to sufficient sanitizing radiation for a predetermined level of sanitization. At least one trough preferably is an irradiation tray oriented so the liquid flows from a first end to a second end with a down pipe located at the second end and a diffuser at the first end. The sanitizing radiation source is an array of UV light sources. Preferably, the sanitizing radiation source is at least two horizontal rows of four UV light sources. In still another embodiment, the apparatus is modular in design.
The invention also comprises a method for sanitizing a liquid within a compact, efficient, easy-to-maintain enclosable apparatus, comprising the steps of providing an ingress for the liquid into a cabinet body, directing the liquid along a plurality of troughs so that the liquid travels along a predetermined vertical and horizontal path within the cabinet body; and subjecting the liquid to one or more sanitizing radiation sources for a predetermined time while flowing along the predetermined path, whereby the liquid is subject to sufficient sanitizing radiation for a predetermined level of sanitization. In another embodiment, the method includes the step of providing an egress for the liquid after exposure to the sanitizing radiation.
It is an object of this invention to provide an apparatus designed with modularity in mind, to suit the processing of different foods or food additives, thereby making it economically beneficial to manufacture in assembly line fashion.
It is also an object of this invention to provide an apparatus in which the radiation sources as well as the paths for the liquid to be sanitized are optimized for radiation treatment and are highly modular in design.
It is also an object of this invention to provide a system for sanitizing a liquid that treats the liquid as a thin film, governed principally by its surface tension, thereby allowing sanitization of the liquid even having a relatively high opacity with regard to the sanitizing radiation.
It is also an object of this invention to provide a compact apparatus for sanitizing a liquid that is easy to assemble, clean, maintain and disassemble.
It is also an object of the invention to provide an apparatus using sanitizing radiation, which is compact and enclosable, so high levels of the radiation may be used in a small amount of space and still be safe for operators.
It is also an object of this invention to provide an apparatus which takes advantage of the flowing characteristics of a liquid to form a cascade in a sanitization process, thereby reducing the amount of mechanical parts or pumping action required.
It is also an object of the invention to reduce the horizontal length necessary to irradiate a liquid.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings.